When people talk about Horse Guards they usually think of the gravel parade ground where the military bands do Beating Retreat, but the best part is actually the small courtyard that faces onto Whitehall. That's where you'll find all the horses and foot soldiers.

Everyone loves a horse. Especially when it's got a soldier on top. If you put a soldier with a shiny sword on top of a horse then you can keep the tourists happy all day.

When the horses are out between 10 AM and 4 PM this place is packed full of happy, snapping, camera clicking visitors, all taking it in turns to tiptoe up to the horse and hoping it doesn't kick them in the goolies. It's probably the most dangerous thing they do all week: standing two feet from a military horse whilst their buddy blinds it with a camera flash. I don't know how the horses abide it -- it must drive them nuts. And it's even worse for the Foot Guards (the standing soldiers), because they haven't even got an animal tank to sit on. They just have to stand there all day watching the tourists do mock marches and limp-waisted salutes, and getting laughed at to smile and say cheese by a class of foreign students. Students always laugh when they salute a soldier. That's because most of them are socialists.

There was a time, not so long ago, when you could actually stand side-by-side with the Foot Guards, but they don't allow that anymore with the world the way it is. They are safely stationed behind a wire chain these days, and if you go beyond the line then you will get barked at -- loudly. These guys can shout louder than a plane taking off. They've also placed a couple of machine gun coppers inside the courtyard whenever the troops are out -- another sad sign of the times. It really is coming to something when our soldiers need a bodyguard.

You might be wondering why the soldiers are standing there at all -- surely it can't just be to entertain the tourists? Once upon a time this building used to be the headquarters of the British Army, and the Household Cavalry still retain a stables in the building. The rest of the generals moved out years ago, to be replaced by government bureaucrats. Most of the windows around the parade ground will have a civil servant in, occupying the same rooms that Wellington wandered around all those years ago.

Have a walk through the central arch and stand in the centre of the parade ground. Can you see that grand facade on the left? That's Admiralty House. Back when Horse Guards was the headquarters of the British Army this building was home to the Navy. Nelson would have been in and out of there at the same time as the Duke was walking around Horse Guards -- they even met once, for the only time in their life, sitting outside one of the offices.

The most interesting building to me is the one next door: the ugly one. The brown concrete box that looks like an eyesore. Sometimes it's covered in green ivy, sometimes in red ivy, but most of the time it's just a pile of dirty brown breeze blocks. I usually want to knock down all the ugly buildings, but I'm prepared to make an exception for this one because of its history. This is the Citadel, and Churchill ordered it to be built so the Admiralty could have a bomb proof operations centre during World War II. Here is definite proof of how close we came to invasion in 1941: if you look at the top righthand corner then you can see some machine gun holes where the soldiers would have fired from.

The rest of the buildings around the parade ground are nice looking, but rather uninteresting for a tourist -- all of them, that is, apart from the Georgian townhouse that's hidden behind a brown brick wall. Can you see that wall on the righthand side, with the big trees behind it? Where the gun cops are guarding? That is actually the wall around the garden of Downing Street. No.10 itself is further back, tucked away in the corner (beyond that white building), so you can't peer into the windows and see what the Prime Minister is doing. I suppose you could bring a big step ladder and a pair of binoculars with you, but I don't recommend that -- those gun cops will probably shoot you.

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